1. Field of the Invention
The present invention relates to a brake actuating device for use in a tape recorder such as a video cassette tape recorder, a digital audio tape recorder and the like, which perform recording and reproducing functions by use of a magnetic recording tape and more particularly, to a brake actuating device for allowing a tape loading operation to be performed in a state that a proper tensional force is applied to a tape by rotating a supply reel while applying a proper braking force to the supply reel and restraining the rotation of a take-up reel during a tape loading operation.
2. Description of the Prior Art
A conventional brake actuating device for use in a tape recorder is illustrated in FIG. 1. A cam 63 is rotatably mounted at the rear side of a supply reel 61 and a take-up reel 62 and between the supply reel 61 and the take-up reel 62, a pair of main brakes 64 and 65 are pivotably mounted which are actuated by a first lever 66. And, a center gear 67 is rotatably mounted in front of the main brakes 64 and 65, which is engaged with a first gear 69 having an operational member 68. A second lever 70 is pivotably mounted which is interlocked with the operational member 68 of the first gear 69 and a first soft brake 71 is pivotably mounted which is interlocked at its one end with the second lever 70 and is adapted to apply a braking force to the supply reel 61 depending upon the pivotal operation of the second lever 70. In addition, a second gear 72 is provided to be engaged with the cam 63 and a second soft brake 73 is provided which is adapted to apply a braking force to the supply reel 61 in response to a rotational torque of the second gear 72. Also, a cam lever 74 is pivotably mounted which is interlocked at its one end with the cam 63 and at its other end with a third lever 75 which is adapted to actuate the second lever 70.
In such a conventional brake actuating device, when a tape is loaded, the main brakes 64 and 65 are pushed by the first lever 66, which is actuated by a separate power source(not shown), so as to be separated from the supply reel 62 and the take-up reel 63, respectively, and the cam 63 rotates clockwise, thus rotating the second gear 72 counterclockwise. As a result, the second soft brake 73 is rotated clockwise by the rotational torque of the second gear 72, thereby being separated from the supply reel 61. Meanwhile, the center gear 67 is rotated counterclockwise by a separate power source to rotate the first gear 69, and by the rotational torque of the first gear 69, the second lever 70 is rotated clockwise to rotate the first soft brake 71 so that the first soft brake 71 applies a braking force to the supply reel 61. That is, since the supply reel 61 is locked so as not to be rotated while the braking force is released from the take-up reel 62, in the course of loading a tape, the take-up reel 62 can be rotated freely by the releasing force of tape.
On the other hand, under the tape unloading operation, the center gear 67 is rotated in clockwise and the first gear 69 is rotated in counterclockwise so that the second lever 70 is rotated in counterclockwise by the rotational torque of the first gear 69. As a result, the first soft brake 71 is separated from the supply reel 61. At this moment, since the cam 63 rotates in counterclockwise, the second gear 72 is rotated in clockwise so that the second soft brake 73 applies a braking force to the supply reel 61, thereby the supply reel 61 is in a locked-state.
Accordingly, such a conventional brake actuating device requires two soft brakes 71 and 73 to apply a braking force to the supply reel 61. That is, in the interval of releasing the second soft brake 73, the supply reel 61 is braked by the first soft brake 71 while in the interval of releasing the first soft brake 71, the supply reel 61 is braked by the second soft brake 73.
However, such a conventional device has disadvantages in that since the number of required brakes is large and a number of levers are required for actuating the brakes at predetermined times, the whole mechanism is complicated and the cost becomes high.